Dark parts of American history are often swept under the rug for being too shameful and painful. But engaging with that history is crucial to understand the present — and figure out how to move forward.

A new website, called Monroe Work Today, is bringing the harrowing history of lynching in the United States out of the shadows. Its detailed map and other resources document the names and experiences of nearly 5,000 people of color who were killed between 1835 and 1963.

“History class taught you the tip of the iceberg,” the site reads. “Every citizen has a duty to know this story. This history belongs to everyone.”